Interval timer



Oct. 2, 1934. G. BROWNING 1,975,347

INTERVAL TIMER Filed July 30. 1931 4 Sheets-Sheet l Oct. 2, 1934. G. BROWNING 1,975,347

INTERVAL TIMER Filed July 30, 1931 4 Sheets-Sheet 2 Oct. 2, 1934. BROWNING 1,975,347

INTERVAL TIMER Filed July 30. 1931 4 Sheets-Sheet 3 Patented Oct. 2, 1934 i INTERVAL TIMER George Browning, Wilmette, 111., assignor to Chicago Flexible Shaft Company, Chicago, Ill., a

corporation of Illinois Application July so, 1931, Serial N... 553,925

16 Claims. (c1. zoo-as),

This invention relates to clocks, and is principally concerned with an improved interval timing mechanism therefor.

The principal object of my invention is to provide a timing mechanism in which a single knob is provided for setting the clock to time a predetermined interval, the said knob cooperating with a single pointer arranged to be turned in one direction from a zero point for a setting of hours, or in the other direction for a setting of minutes, both scales being provided on a single dial reading both ways from the zero point. This greatly facilitates the matter of setting since the same knob is operated for either kind of setting and there is no possibility whatsoever of confusion, it being necessasry to turn the lcnob in one di? rection for an hour setting and in the opposite direction for a minute setting.

Another object is to provide a mechanism in 29 which practically all of the operating parts are concentrically disposed on one stem that is arranged to be turned by the aforesaid knob, thus making for the best compactness obtainable, so that the mechanism together with the clock associated therewith can be made to fit in a relatively small case of neat and attractive appearance.

Still another object is to provide a mechanism embodying spring means arrangedto beloaded in the turning of the knob in setting, whereby to relieve the clock mechanism of any appreciable dragin its operation of the mechanism. The spring means is furthermore so arranged that it becomes disassociated witli the parts with which the same is otherwise arranged to "cooperate when the pointer of the timing mechanism is between the two zero points of the hours and minutes scales, thereby avoiding any danger of the spring means interfering with the clock keeping accurate time. The invention is illustrated in the accompanying drawings, in which Figure 1 is a face view of a clock embodying the interval timer of my invention;

Fig. 2 is a back view;

I Fig. 3 is a central longitudinal section as indicated by the line 3-3 of Figure 1, the view being on a larger scale;

Fig. 4 is a cross-section in the plane of the line 4-4 of Fig. 3;

Figs. 5 and 6 are sectional details on the correspondingly numbered lines of Fig. 3:

Fig. 7 is a view similar to Fig. 6 showing certainparts in a shifted position;

Fig. 8 is an enlarged horizontal sectional tail on the line 8-8 of Fig. 6;

line 9-9 of Fig. 3;

.the interval is being timed for.

Fig. 9 is a cross-section similar to Fig. ion the Fig. 10 is'a view cor-responding to a portion of Fig. 9 showing the parts in shifted position;

Fig. 11 is 'an-enlarged sectional detail on the 90 line 1l-11 of Fig. 9 showingthe mechanism on a minute setting, and

Fig. 12 is a section on the line 12-12 of Fig. 9 showing the mechanism on an hour setting.

The same reference numerals are applied to corresponding parts throughout the views.

The invention is herein illustrated in connection with an electric clock, but it will soon appear that any form of clock mechanism could be used, although there is, of course, the advantage with the electric clock of utilizing the same circuit for theelectrically-operated alarm of the interval timer. Furthermore, while an alarm as herein illustrated is arranged to be sounded at the predetermined interval for which the clock may be set, it should be understood that any other device could be arranged to be operated instead or at the same time, depending on what For example, doctors, research engineers, housewives, and others engaged in work frequently requiring accurate measurement of predetermined time intervals, are ordinarily satisfied with the sounding v of an audible alarm at the end of a predetermined time interval for which the clock may be set. In some cases, however, especially in certain industries, clocks of this kind are frequently desired to throw some device into or out of operation automatically at a predetermined interval, and in such cases it will be obvious that instead of the electrically-operated alarm, or, in

addition to it, an electric relay or the like will be provided to control the device in connection with which the clock may be provided.

Referring generally to Figs. 1-3, the numeral 10 is applledto the case for the clock, indicated generally by the reference-numeral 11, and-the interval timer indicatedjgenerally by'the reference numeral 12. The clock 11 is herein illustrated as being an electric clock of conventional construction having its frame plates 13 suitably supported on the front plate 14 immediately behind a separate face plate 14' on which the regular clock dial 15 is provided. 16 is the field coil of the electric clock' 11 carried on one of the frame plates 13 and cooperating with the usual armature provided in the housing appearing at 17. The back plate 18 carries a receptacle 19 for an electrical attachment plug 20 having an extension cord 21 thereon. Wires 2 and 23 are extended front the of the receptacle 19 f to the coil-16, as best appears in Fig, 9, for the operation of the clock. "Other wires'zd and are extended from the same terminals to the in-= tervel timer 12 for the operation of the electricel clapper mechanism 26 of the alarm bell 2'7,

' as will soon eppeer.v .In passing, itwill be ob served that the clock 11 has the usual hour hand 282.1111 minute hand 29, and also as second hand 30, ell cooperating with the dial 15 end protected by the gloss front 31. 32 is e starter stem, end

. 33 a setting stem eccessible on the heck of the ole-cl; in the usual way. The clock is arranged to be suspended on the well by means of the log to provided on the beck. r

. The nice oi the interval timer'lfi depends for its operation upon e minute gear 35 which meshes with e. gear 38 fixed on the some it with e. gees 37. A pinion,38 meshing with the gear 37 is thereby arranged to drive e periph- 'erellyserreted friction drive wheel 39, which will hereinafter be referred to es the minute wheel. The pinion-38 and minute wheel 39 have s coon hub end are mounted for rotation on the stem. to which extends through the. case 10 from front to heck end finds bearing support in the face plate is at its front end, end at its rear end in another piste oi supported, us appeers'at 42.11 m their-sine 13 at its upper end end at its lower end from the front, plate it, as st 43. 'lhe stem to projects through a hole ii in the glass front 31 and hes a knob 45 fixed on the:

projecting end thereof, this knob being hereineftcr'rei'erred to us the setting knob of the interval timer. A pointer 66 is fixed on the stem to cooperate with e'diel 47 of substantially semicircular form provided on the face plate 14' below the regular clock dial 15. The dial thee when will be noticed, is graduated half in hours and half in minutes reading in opposite directions from the two zero points at the middleof the dial suitable number of hours and any number of minutes of course, be provided for onfthe dial e7. Another gear 48, similar to theigeer 38, is provided for driving e peripherally serrated friction drive wheel 49,"

hereinafter to be referred to es the hour wheel.

The gear s8 and wheel i9 have a common hub mounted for rotation-on the-stem Q0. The gear 48 is driven through reduction gearing by the 7 gear 38 so' that the speed of the hour wheel 49 is in proper proportion to the speed of the minute wheel 39; and so that the hour wheel is turned in e counter-clochwise direction as viewed from the face of the clock, whereas the minute wheel turns in e clockwise direction. Thus e large gear 50 mesheswith the gear 38 to turn the sheft 51 on which a smell pinion 52 is provided. The letter meshes with gear 53 which in turn drives the small pinion 5e meshing with the gear to. The gear 53 and pinion 5e are in a cluster mounted on a. suitable spindle on c, plate 55 supported by bolts 56 from the plate d1. Now, the stem 40 is arranged tobe turned by means of the setting knob 45 in o. counter-clockwise direction for a. minutesetting, and in o clockwise direction for an hour setting, and when so turned is arranged to be automatically clutched orses? and another hooked end for frictional driv-' ing eng ement with the periphery of the hour f wheel 4.9. When the stem 40 is in a, mid-position, that is, with its pointer es between the two zero points tit the middle of the diele'l, the clutch 57 is in c mid-position disengaged with relation to both of the wheels 39 end 49, as shown in Fig. 3, but when the stem 40 is turned to make a setting, it is also shifted endwise automoticoliy in the proper direction to engage the clutch with the proper wheel. The clutch shifting moons comprises at pin 61 projecting radielly from the stem to end having e roller 62 on the outer end thereof which is arranged to run on o track provided on e plate. 63 disposed on one side of the pin, or on it track provided on another plote do 'd on the opposite side of the pin. The plates 63 ended are of segmental form, as best eppeorsin Figs. 6 end 7, and are supported on the bolts 56 between the plates 41 end 55, small spacers being provided on the bolts 56, as best illustrated in Figs. 8 and Il, to hold the plates 63 end 64 in proper speced relep tion to the plates c1 and 55, respectively, and also in proper spaced relation to one another. E-l- When the stem 40 is turned in a, counter-clockwise direction, the roller 62 on the pin 61 en" counters a com surface on e rearwerdly bent lug 65 provided'on the plate 63 and shifts the clutch 57 with the stem to forwardly, whereby to en-' gage the minute wheel 39. The end 69 of the leaf spring forming the clutch 57 is bent inthe proper direction with relation to the direction of rotation of the wheel 39 so that the same will ride idly over the serrated periphery as the stem 40 is turned to bring the pointer 46 to whatever setting is desired on the minute section of the diel 4.7. On theother hand, when the stem 40 is turned in a clockwise direction, the roller 62 on the pin 61 encounters a, com surface provided on a forwardly bentlu g fid on the plate as and causes the clutch 57 tobe-shifted reerwardly with the stem 40 to engage the hour wheel 49. The end 60 of the leaf spring forming the clutch 57 is bent in the opposite direction with respect to the end 59 so that it is arranged to ride idly over the serrated periphery of. the hourwheel es the stem 40 is turned to bring the pointer 46 to the desired setting on the hour section of the dial -47. While the ends 59 and 60 ere arranged due to their resilience to ride idly over the peripheries of the wheels 39- and 49, respectively, in setting, there is, no likelihood of slippage in the driving of the'stem to through the clutch 57 by said wheels, due to the fact that the stem 40 is given enough movement in the cumming of the pin 61 to bring the clutch 57 into engagement with the minute or hour wheel with sumcient pressure tofinsure a good friction drive.

When the pointer 4.6 is in the mid-position shown in Figure 1, between the two zero points, the pin 61 is in the position shown in Fig. 8 and the clutch 57 is, of course, disengaged, so that there is obviouslv no perceptible drag imposed on the operation of the clock 11. The wheels .39 1g) and 49in that case are simply turning idly. However, as soon as the stem 4.0 is turned for either an hour or a minute setting, a load is imposed which, though light, might be enough to interfere with the clock keeping accurate time. This load is due to the frictional resistance of the roller s2 riding on the track on either of the plates 63 and 64 under the spring ,pressure of the clutch 57. To offset this load,'I provide two..

coiled torsion springs 67 and 68, theformer of which is two bolts :so that either spring is tim arranged to actin a clockwise direction to aid in, the return of the stem 40 to zero position when the same has been turned in a'coimi tar-clockwise direction for the other or which counter-clockwise direction to aid in the return of the stem 40, to zero position when the stem has been turned in a clockwise direction for an a minute setting, and

' 10' hour setting. The two springs are coiled about the stem 40, as best appears in Fig. 11, with their one ends in abutment with-the upper one of the to 56. A pin 69 proiects from the plate 67, and in a similar manner a pin projects from the plate 41 for cooperation with the spring 68, whereby to hold the springs under an initial tension while they are inactive, namely, when the pin 61 is in mid position, as shown in Fig. 6, and arranged to be rendered activedepending on which way the pin 61 is moved-from mid position. In other words, the two springs 67 and 68 are disassociated with relation to the timing mechanism except when the stem 40 has been turned by means of the setting lmob 45 for any given time interval setting, and the spring pressure or either of these springs against the pin 61 is enough to chest the triotional resistance to the riding of the roller 62 on the tracks provided therefor, so that the clock mechanism has no perceptible drag imposed on its operation, and the clock will keep accurate The stem 40, in addition to carrying the pointer 46, the clutch 57, and the driving wheels 39 and-10 cooperating with the latter, as well as the clutch shifting means at 61, carries a swinging contact arm 71 fastened as at 72 onto the fiattened rear end portion 73 of the stem. A contact 74 is carried on the arm 71 on the insulation indicated at 75, and is arranged to brush against the sharply bent portions 76 and 77 of a pair of leaf spring contacts 78 carried, on the plate 41 in insulated relation thereto. The wire 24 previously referred to is connected with one of the leaf spring contacts 78, and another wire 79 extending from the clapper mechanism 26 of the alarm hell 2'? is connected with the other 0! said contacts, so that when the contact 74 rides over the bend 76 or 77, the circuit'through the clapper mechanism is completed to sound the alarm. When the pointer 46- is in mid position between the two zero points of the dial 47, the contact 74 is midway between the bends 76 and 77, as illustrated in Fig. 9. 45 in either direction for an hour or minute setting causes the contact 74 to sweep past either of the bends 76 and 77 as the pointer passes the zero point, and then the contact 74 is slowly returned as the pointer 46 slowly returns to its initial position, until finally the contact 74 comes into engagement with the bends of the contacts 78 at the moment that the pointer 46 reaches the zero point, whereupon the alarm is sounded by reason of a circuit being completed through the clapper mechanism 26. In the setting of the pointer 46, as the contact 74 brushes past the bend 76 or 77, as the case may be. there is, of course, a momentary sounding of the alarm, but the contact moves more slowly in its return and makes Contact at 76 or 77 for several seconds so as to give a good alarm. It is shortly after breaking of contact at 76 or 77 that the clutch 57 is disengaged by reason of the roller 62 riding olf the track on the plate 63 or 64.. In Fig. 10 the arm 71 is illustrated in full lines holding the contact is arranged to act in a serve as a stop for the other end oi the springv However, turning of the knob 74 in a position corresponding to an hour setting or the pointer 46. Theway in which the contact 74 makes engagement with the contacts 78 at 76 is indicated in dotted lines.

It is believed the ioregoi'ng description conveys a good understandlngor the objects and advan' tages of my invention. The appended claims have been drawn so as to cover all legitimate modifica-" tions and adaptations. It should be understood that while I have disclosed an interval timer designed for the timing oi intervals in minutes or hours, the device could be changed easily ior the purpose of timing intervals in minutes or seconds. The term minutes should, therefore, be construed broadly as meaning a small time interval, and the term hours a larger time interval. In other words, "hours and minutes arepurely relative terms and are not to be regarded in a limitingsense.

I claim:

- 1. In a clock, a dial having one section for smaller units or time reading in one direction troma zero point and another section for larger units ogz'time reading in the opposite direction from another zero point, a pointer movable manually relative to the dial from a normal position between the two zero points selectively in either direction for a setting of larger or smaller units of time, a clock mechanism, pointer driving connecting the pointer driving means with the clock mechanism in the setting oi-the pointer in either of the two dial sections, whereby to return the pointer toward the zero point of that section, in timed relation to the operation of the clock mechanism, said means automatically discon necting the pointer driving means from the clock mechanism after the pointer has passed the zero point and arrived at its normal position between the two zero points.

2. In an interval timing cloch the combination with the. conventional clock dial and hands therefor, and clock mechanism for operating the hands, of a secondary dial having a section for smaller units of time reading in one direction from zero and another section for larger units or time reading in the opposite direction from zero, a pointer arranged to be turned manually from a normal zero position selectively in either direction for a 125 ated by the clock mechanism to move the pointer in timed relation to the operation of the clock back to the zero point in one direction for a no setting of smaller units of time and in the opposite direction i'or a setting of larger units of time. 3. In an interval timing clock, the combination with the conventional clock dial and hands therefor, and clock mechanism for operating the hands, of a secondary dial having a section for smaller units of time reading in one direction from zero and another section for larger units of time reading in the opposite direction from zero, a pointer arranged to be turned manually from a normal zero position selectively in either direction for a setting of large or small units of time for any predetermined time interval, means operated by theclock mechanism to move the pointer in timedrelation to the operation of the clock back to the zero point in one direction for a setting of the smaller units of time and in the opposite direction for a setting 01 the larger units of time, spring means active in one direction rendered operative in the setting of the pointer in the first section of the secondary dial to assist the clockoperated means to return the pointer to zero whereby to, proportionately relieve the clock mechanism of a drag on its Operation, and another spring means active in the Opposite direction and rendered operative in the setting of the pointer in the other section of the secondary dial to assist the clock-operated'means to return the pointer to zero whereby to proportionately relieve the clock mechanism of a drag on its operation.

4. In an interval timing clock, the combination with the conventional ,clock' dial and hands therefor, and clock mechanism for operating the hands, of a secondary dial having a section for smaller units of time reading in one direction from zero and another section for larger units of time reading in the opposite direction from zero, a pointer arranged to be, turned manually from a normal zero position selectively in either direction for a setting of large o'i' 'small units of time for any predetermined time interval, means operated by the clock mechanism to move the pointer in timed relation to the operation of the clock back to the zero point in one direction for a setting of the smaller units of time and in the opposite direction for a setting of the larger units of time, and spring means rendered operative in the setting of the pointer on the secondary dial to assist the clock-operated means to return the pointer to zero whereby to proportionately relieve the clock mechanism of a drag on its operation.

5. In an interval timing mechanism, the combination of a dial having a section forsmaller units of time reading in one direction from zero and another section for larger units of time reading in the opposite directionjrom zero,-a setting stem having a pointer thereon cooperating with the dial and arranged to be turned in either direction from zero to set the pointer for a predetermined time interval of larger or smaller units of time, a first wheel related to the first section of the dial turning freely on the stem, a second wheel related to the other section of the dial turning. freely on the stem, means for driving said wheels in opposite directions at difierent predetermined speeds, and means for clutching the stem to either wheel whereby to turn the pointer in one direction relativeto the first section back to zero and in the opposite direction relative to the other section back to zero.

6. In an interval timing mechanism, the combination of a dial havinga section for smaller units of time reading in one direction from zero and another section for larger units of time reading in the opposite direction from zero, a setting stem having a pointer thereon cooperating with the dial and arranged to'be turned in either direc-' tion from" zero to set the pointer for a predetermined time interval of larger or smaller units of time, a first wheel related to the first section of the dial turning freely on the stem, a second wheel related to the other section of the dial turning freely on the stem, means for driving said wheels in opposite directions at different predetermined speeds, a clutch element on the stem between the first and second wheels and arranged upon axial movement of the stem in one direction to clutch the first wheel and upon axial movement of the stem in the other direction/to clutch the second wheel, and clutch shifting means cooperating with the stem so that when the stem is turned to set the pointer in the first section of the dial, the stem is moved in one direction to clutch the first wheel, and so that when the stem is turned in the opposite direction to set operating therewith in the turning of the stem in one direction to move the stem endwise in a certain direction, and another abutment cooper ating therewith inthe turning of the stem in the other direction to move the stem endwise in the opposite direction.

8. In a mechanism as set forth in claim 6 wherein the clutch shifting means comprises a pin projecting radially from the stem, an abutment cooperating therewith inthe turning of the stem in one direction to move the stem endwise in a certain direction, another abutment cooperating therewith in the turning of the stem in the other direction to move the stem endwise in the opposite direction, the device including a torsion spring on the stem-to cooperate with the pin upon movement thereof "in one direction to urge the pin back to normal position, and another torsion spring on the stem to cooperate with the pin in the movement thereof in the opposite direction to urge the pin back to normal position.

9. In an interval timing mechanism, the combination of a dial having a section for smaller units of time reading in one direction from zero and another section for larger units of time reading in the opposite direction from zero, a setting stem having a pointer thereon cooperating with the dial and arranged to be turned in either direction from zero to set the pointer for a predetermined time interval of larger or smaller units of time, a. first wheel related to the first section of the dial turning freely on the stem, a seconda determined speeds, means for clutching the stem to either wheel whereby to turn the pointer in one direction relative to the first section back to -zero and in the opposite direction relative to the other section back to zero, a stationary electrical contact, and a movable electrical contact carried on said stem and arranged to be turned with the stem in the setting thereof to a position spaced in either direction relative to the stationary contact according to the setting of the pointer, the movable contact'being arranged to engage the stationary contact upon return oi. the pointer to zero.

10. In ,a mechanism as set forth in claim 6 wherein the clutch shifting means comprises a pin projecting radially from the stem, an abutment cooperating therewith in the turning of the stem in one direction to move the stem endwise in a certain direction, another abutment cooperating therewith in the turning of the stem in the other direction to move the stem endwise in the opposite direction, and spring, means rendered operative in the setting of the pointer to cooperate with the pin to urge the same back to normal position.

11. In an interval timing mechanism, the combination of a dial graduated for smaller and larger units of time, both graduations reading from zero, a setting stem having a pointer thereon cooperating with the dial and arranged to be turned to set the pointerin a predetermined spaced re-v turning freely on the stem, a second wheel related to the larger units on the dial turning freely on the stem, means for driving said wheels at different predetermined speeds, the ratio of which is'proportional to the ratio of the smaller and larger units of time, and means for clutching the stem to either wheel whereby to turn the pointer quickly back to zero in a setting for smaller units of time and slowly back to zero in a setting for larger units of time.

12. Inaninterval timing mechanism, the combination of a dial graduated for smaller and larger units of time, both graduations reading from zero, a setting stem having a pointer thereon cooperating with the dial and arranged to be turned to set the pointer in a predetermined spaced relation to the zero point tor a predetermined time interval of larger or smaller units of time, a first wheel related to the smaller units on the dial turning freely on the stem, a second wheel related to the larger units on the dial turning freely on the stem, means for driving said wheels at different predetermined speeds, the ratio of which is proportional to the ratio of the smaller and larger units of time, a clutch element on the stem between the flrst and second wheels and arranged 'upon axial. movement of the stem in one direction to clutch the first wheel and upon axial movement of the stem in the other direction to clutch the second wheel, said stem being moved in one direction for a setting of smaller units and in the other direction for a setting of larger units, said pointer being thereby moved quickly back to zero in a setting for smaller units and slowly back to zero in a setting for larger units, and means for automatically disengaging the clutch element after the pointer has returned to zero.

13. In an interval timing mechanism, the combination of a. dial graduated for smaller and larger units of time, both graduations reading from zero, a setting stem having a pointer thereon cooperating with the dial and arranged to be turned to set the pointer in a predetermined spaced relation to the zero point for a predetermined time interval of larger or smaller units of time, a first wheel related to the smaller units on the dial turning freely on the stem, 8 second wheel related to the larger units on the dial tuming freely on the stem, means for driving said wheels at difierent predetermined speeds, the ratio 01 which is proportional to the ratio of the smaller and larger units or time, means for clutching the stem to either wheel whereby to turn the pointer quickly back to zero in a setting for smaller units or time and slowly back to zero in a setting for larger units of time, and spring means rendered operative in the setting of the proportional to the ratio of the smaller and larger units of time, and means for selectively clutching the pointer to either member to move the pointer relatively quickly back to zero in a setting for smaller units of time and relatively slowly back to zero in a setting for larger units of time.

'15. In an interval timer, the combination of a clock mechanism, a dial graduated for smaller and larger units of time, both graduations reading from zero, a pointer movable manually to a predetermined spaced relation to the zero point for a predetermined time interval of larger or smaller units of time, and means operated by the" clock mechanism for moving the pointer in timed relation to the operation of the clock back to the zero pointrelatively slowly for a setting of larger units of time and relatively quickly for a setting of smaller'units of time.

, 16. In an interval timing clock, the combination with the conventional clock dial and hands therefor, and clock mechanism for operating the hands, or a secondary dial having a minutesection reading in one direction from zero. and an hour section reading in the opposite direction from zero, a pointer arranged to be turned manually from a normal zero position selectively in either direction for a setting of minutes or hours for any predetermined time interval, and means operated by the clock mechanism to move the pointer in timed relation to the operation of the clock back to the zero point in one direction for a setting of minutes and in the opposite direction for a setting of hours.

GEORGE BROWNING. 

